Overview of Environmental and

Hydrogeologic Conditions at Chandalar Lake, Alarka

.. - .

U.S. GEOLOGICAL SURVEY

Open-File Report 95-348

Prepared in cooperation with the

FEDERAL AVIATION ADMINISTRATION

Overview of Environmental and

Hydrogeologic Conditions at Chandalar Lake, Alaska

By James R. Cowan

U.S. GEOLOGICAL SURVEY

Open-File Report 95-348

Prepared in cooperation with the

FEDERAL AVIATION ADMINISTRATION

Anchorage, Alaska 1 995

U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY Gordon P. Eaton, Director

For additional information write to: Copies of this report may be purchased from:

District Chief U.S. Geological Survey U.S. Geological Sunrey Earth Science lnfomation Center 4230 University Drive, Suite 201 Open-File Reports Section Anchorage, AK 99508-4664 Box 25286, MS 51 7

Fedem! Center Denver, CCO 80225-0425

CONTENTS

................................................................. Abstract 1

Introduction ........ ... .................................................. 1

................................................................ Background 1

h a t i o n .............................................................. 1

.............................................. History and socioeconomics 3

............................................................ Physical setting 3

.............................................................. Climate 3

............................................................ Vegetation 3

........................................... Geology ............. .... 4

................................................................ Hydrology 5

Surfacewater ......................................................... 5

.......................................................... Ground water 7

............................................................. Drinking water 8

Suwnary ................................................................. 8

References cited ............................................................ 8

FIGURES

1 . Map showing location of Chandalar. Alaska. and the Federal Aviation Administration facility .................................................

2 . Hydrograph showing discharge of the Middle Fork Koyukuk River near Wisemar. wateryear1978 ......................................................

1 . Mean monthly and annual temperature. precipitation. and snowfall for the period 1968-87. Federal Aviation Administration facility. Chandalar Lake ............. 4

2 . Computed average and minimum streamflowfor streams near the Federal Aviation Administration facility. Chandainr Lake ................................... 6

CONVERSION FACTORS, VERTICAL DATUM, AND ABBRNIAIIONS

centimeter Icm) 0.3937

kilometer Ikm) 0.6214

square kilometer (b2) 0.5861

cubic meter pet m u d (rn3/s) 35.31

liter per day Wd) 0.2642

indl

iach

fDot

mile

square mile

cubic foot ptr secwd

P ~ F & Y

degree Ctlsius PC) T=1,8 eC)+32 degreeFal~d~i teF)

se&u& In ?his report, "sea level" refers to the National Geodetic Vertical Datum of 1929-A @tic datum dxived h m a general adjustment of the first-order level nets of the United States and Canada, formerly called Sea Level Datum of 1929.

Abbreviated water-oualitv unit w i n thlsrennrt;

(pg/L), microgram per liter

Overview of Environmental and Hydrogeologic Conditions at Chandalar Lake, Alask

By James R. Cowan

Abstract

The ~ e d e d Aviation Administration facility at Chandalar Lake is on the east shore of the lake in the eastern Brooks Range of Alaska. The Federal Aviation Administration is amsidering the severity of contamination and the environmental conditions near their Chandalar Lake facility when evaluating options for compliance with environmental regulations. 'She area has long cold winters and short cool summers. Roods are not a significant threat at the facility. The facility and a nearby private lodge currently obtain drinking water from Chandalar Eake. Altemativc drinking- water sources may be available, but little is known about the quantity or quality of there, sources. Surface spills and disposal of hazardous materials, should they occur, could affect the quality of the surface water and ground water in the area.

INTRODUCTION

The Federal Aviation Administration (FAA) owns and (or) operates airway support and nav- igational facilities throughout Alaska. At many of these sites, fuels and potentially hazardous mate- rials such as solvents, polychlorinated biphenyls, and pesticides may have been used and (or) disposed of. To determine if environmentally hazardous materials have been spilled or d:cm)sed of at the sites, the FAA is conducting environmental studies mandated under the Corn~mhensive Environmental Response, Compensation, and Liability Act and the Resource Consenration and Recovery Act. To complete these more comprehensive environmental studies, the FAA requires information on the hydrology and geology of areas surrounding the sites. This report, the product of compilation, review, and summary of existing hydrologic and geologic data by the U.S. Geolog- ical Survey (USGS), in cooperation with the FAA, provides such information for the FP A facility and nearby areas at Chandalar Lake, Alaska. Also presented in this report is a description of the history, socioeconomics, and physical setting of the Chandalar Lake area.

BACKGROUND

Location

The FAA Chandalar Lake facility is in the Brooks Range in northeastern Alaska at approxi- mate latitude 67'30' N. and longitude 148"29' W (fig. I), The elevation of the facilit:. is about 585 m above sea level. The facility is approximately 300 km north of Fairbanks and a b ~ t 300 krn south of Deadhorse. The Dalton Highway-TransAlaska Pipeline corridor is about 60 k-n west of the facility. The FAA facility is on the east shore of Chandalar Lake, a natural impoundn*snt of the North Fork of the Chandalar River in the Yukon River drainage basin, The FAA Chanclalar Lake facility should not be confused with tbe Chaadalar Shelf airfield at the ChandaZar pipeline camp approximately 80 lm to the northwest.

1 2 MILES I 1 I

-5 1 2 KILOMETERS

Figure I. Location of Chandalar, Alaska, and Federal Aviation Administration facilities.

2 Ovennw of Envlmmental and Hydr~gWoglc Condtrane at Chandelar Lake, Alaska

History and Sucheconomics

"Chandalar" is derived from the name given to the Kutchin Indian inhabitants by French trappers employed in the area by the Hudson Bay Company (M, 1967). In the early 1900's, a mining camp was established near Chandalar Lake. A post office was maintained there from 1908 until 1944.

The remote Chandalat Lake airstrip was constructed in the 1950's to support mining activity in the area @I. Kunes, Bureau of Land Management, oral commun., 1995). Today, its p-imary use is as a point-of-entry for hunters, fishermen, outdoor recreationists, and scientists seeking access to the eastern Brooks Range. The FAA has operated a remote navigational facility at Chandalar Lake since 1968 (Ecology and Environment, Inc., 1992). The FAA facility includes a. nondirec- tional beacon antenna and two buildings near the northeast end of the airstrip and a generator build- ing, fuel tanks, and pipeline near the southwest end of the runway. The remote facility is maintained by FAA employees who visit the site about four times a year (Kathleen Ed':, Federal Aviation Administration, written commun., 1995). A detailed account of properties owned, leased, or transferred by the FAA at Chandalar Lake and a listing of suspected sources of contamination near these facilities is in the Environmental Compliance Investigation Report (ECIR) p-epared by Ecology and Environment, Inc. (1992).

Chandalar Lake is principally a recreational area. A privately owned facility, McManus camp, is the only residential area near the FAA Chandalar Lake facility. The McManris camp is located on the eastern shore of Chandalar Lake about 400 m south of the FAA facility and is occu- pied primarily during the summer season. The FAA supplies the McManus camp with electricity (Ecology and Environment, Inc., 1992), Chandalar Lake is without road access, and airccaft are the most common means of access to the FAA facility. A winter trail allows limited surfac.: access to the area (Jack McManus, McManus camp, oral commun ., 1995).

PHYSICAL SETTING

Climate

Chandalar Lake is in the continental climate zone and is subject to large daily an4 seasonal temperature variations (Hartman and Johnson, 1978). Low precipitation, clear skier and low humidity are typical during the long winter; cloudy, humid conditions characterize the short sum- mer. The mean annual temperature is -8.2 "C, but temperatures range from a July mean maximum of 19.9 "C to a February mean minimum of -32.4 "C. Mean totat annual precipitaticn is about 240 mm. July and August are the months of greatest rainfall. Approximately 1,000 mm of snow falls annually. Mean monthly and annual temperature, precipitation, and snowfall data are summa- rized in table 1 (Leslie, 1989).

Vegetation

Vegetation near Chanddar Lake consists of closed spruce-hardwood forest in the valleys and on lower slopes and alpine tundra at higher elevations (Viereck and Little, 1972). Stands of white spruce grow on south-facing slopes, and black spruce grow on north-facing slopes and on poorly drained lowland areas. Undergrowth consists of mosses, grasses, and brush. The alpine tundra areas are predominantly barren with local accumulations of low heath s h b s , white mountnin- avens, and dwarf herbs.

fable 1. Mean monthly and annual temperature, precipitation, and snowfall for the period 1968- 1987, Federal Aviation Administration facility, Chandalar Lake podifid from Leslie (1989); 'C, d e p Celsius; mm, millimeter]

. - .-

Jan. Feb. Mar. Apr. May June July Aug. Sept Oct. Nw. Dec. Ainual

mmpera- W) Meanmaximum -19.6 -18.9 -10.4 -18 102 18.4 19.9 16.4 &3 4 1 -15.1 -19.1 -1.3

maximum 30.6 %, July 1986)

Mtan minimum -31.7 -324 -27.1 -19.1 -3.8 3.6 4.9 12 -39 -14.4 -26.4 -31.0 -15.0

(Record W u m -55.6 %, February 1974)

Mean -25.7 -25.7 -18.8 -10.4 33 11.0 12.4 W 22 -92 -20.8 -25.1 -8.2

hecipitatboa (mm of moistnw) Total

9.7 8.4 7.1 53 10.9 35.6 45.7 41,7 315 19.8 112 11.7 238.3

Snowfall (mm) Total

111.8 109.2 96.5 96.5 20.3 0.0 0.0 0.0 40.6 195.6 154.9 177.8 1,003.3

Geology

Wahrhaftig (1965) includes the area surrounding the FAA Chandalar Lake fac:lity in Ehe centraVeastem Brooks Range area of the Arctic Mountains physiographic province. The nearby glaciated mountains rise to elevations of approximately 1,500 to 1,800 m.

Bmsg6 and Reiser (1964) describe bedrock in this area of the B m k s Range as qwmite- and mica-rich schist of Devonian age. These rocks are well exposed and complexly faulted in the nearby mountains where Devonian volcanic sills and flows are common along fault ard bedding planes in the bedrock sequence. Heavily glaciated, the bedrock is fractured and frost-shattered where exposed. Depth to bedrock beneath the FAA Chandalar Lake facility is unknowr .

The FAA facility is on one of three large fan deltas bordering Chandalar Lake. T:?lle shallow geologic section is composed of alluvial and glacial deposits of late Pleistocene and Holwene age (Hamilton, 1978). In genera!, the stratigraphy of these deposits consists of poorly sorted, sandy to gravelly alluvium overfying till. The thickness of these deposits is unknown.

Ferrians (1965) chmcttrizes this area of Alaska as k ing underlain by continuous perma- frost. Soils near the facility are classified as inceptisols, a soil order in which most p-rmafrost- bearing soils are included (Rieger and others, 1979). Inceptisols include somewhat underdeveloped soils that exhibit only minor modification of the parent material. Soil in the immediate vicinity of the FAA Chandalar Lake facility is a gravelly to sandy loam derived from the surrounding glacial deposits (Schmphorster and Reator, 3973). Highly permeable, this soit retains Iittle moisture and permafrost is either deep or absent. A poorly drained, fine, sandy loam is present in lovf-lying flat areas near Chandalar Lake. This sandy loam is covered by a peaty organic mat about 20 cm thick. The seasonally thawed active layer is as much as 40 cm in thickness and is saturated throughout the summes (Schoephorster and b t m , 1973).

4 Ovewlew of Environmmtai and Hydrogedoglc Conditions el Chendelar Lake, ALaska

HYDROLOGY

Surface Water

The primary surface-water feature at the FAA Chandalar Lake facility is ChanCaIar Lake. This natural impoundment of the North Fork of the Chandalar River is approximately 15 km long and 2 km wide. Several perennial and intermittent streams flow into Chandalar Lake, three of which are within 1 km of the FAA facility. Each of the three nearby streams flows west into the lake from the mountains east of the facility.

Many streams in arctic Alaska flow only during the summer and typically are frozen to the strambed during the winter. The hydrograph showing discharge at USGS streamflow-gaging sta- tion 15564875 on the Middle Fork of the Koyukuk River, near Wiseman (fig. 2), illustrates the characteristic streamflow pattern of many arctic rivers and streams. The gaging station is approxi- mately 75 krn west of Chandalar Lake, is at a similar elevation, and has a drainage basin area (3,100 h2) approximately the same size and character as that upstream from Chandalar Lake (2,700 km2). There is little or no measurable discharge between mid-November and early May. Streamflow tends to peak in June and then declines, with periodic rainstorm peak f ows, until freezeup in November. Average discharge for 8 years of record through water year 197? was 20.1 m3/s (U.S. GeoIogical Survey, 1979).

Flgure 2. Discharge of the Middle Fork Koyukuk River near Wiseman, water year 1978.

There are no stream-discharge data for the North Fork of the Chandalar River or for the three streams near the FAA Chandalar Lake facility. However, the average annual discharg? and low- flow discharge can be estimated using equations developed to characterize the streamflo.~ of rivers and streams in Interior Alaska basins Brabets, U.S. Geological Survey, written cornmun.,

1995). These equations use drainage basin area in square miles and mean annual precpitation in inches to estimate streadow.

The average annual discharge (QAVE) is calculated using:

Where:

AREA is drainage basin area, in square miles; and

PRECIP is mean annual precipitation in the drainage basin, in inches (determined from Jones and Fahl, 1994, plate 2).

March is considered to be the period of low streamflow in Interior Alaska. Many small streams, such as those near the FAA Chandalar Lake facility, freeze to the streambed duing winter and cease to flow. However, an estimate of the low-flow discharge for an Interior Alaqka stream can be made using the following equation:

The computed average and low-flow discharge for the North Fork of the Chandala- River and the three streams near the FAA Chandalar Lake facility are shown in table 2. The metic equiva- lents of the variables and the calculated streamflow values are listed in the table. Because of the paucity of winter streamflow data for rivers and streams of interior Alaska, the standard error of prediction for the computed average and low-flow discharges is relatively high (29 percent and 92 percent, respectively) (T.P. Brabets, U.S. Geological Survey, written commun., 1995). The stan- dard error of prediction is a non-symmetrical function derived by conversion of the 19garithmic units used in the regression analysis to percent (G.D. Tasker, U.S. Geological Survey, witten com- mun., 1978).

Table 2. Computed average and minimum streamflow for streams near the Federal Aviation Administration facility, Chandalar Lake b2, square kilometer; mrn, millimeter; m3's, cubic meter per second; <, less than]

Drainage basin Mean annual Discharge Drainage area precipitation (m3/s)

basin (km2) (mm)

QAVE QMAR North Fork Chandalar River 2,720 685 36 3

Tobin Creek 52 533 < 1 <1

Rosalie Creek 10 533 <1 <1

Unnamed creek 8 533 < 1 <1

The drainage basin area for the river and each of the three streams near the FAA Chandalar Lake facility was estimated from U.S. Geological Survey State of Alaska Map E (1973, rev. 1987) and U.S. Geological Survey Alaska Topographic Series, Chandalar, Alaska (1956, rev. 1982). The largest of the three nearby streams is Tobin Creek which enters Chandalar Lake about 1 krn north of the FAA facility. The FAA Chandalar Lake facility lies within the small drainage basin of an unnamed creek that flows south of the airstrip, between the FAA facility and the McManus camp,

6 Overview of Environmental and Hydrogeologlc Condltlons at Chandalar Lake, Alaska

and into Chandalar Lake approximately 400 m from the facility (fig. 1). Aerial photographs of the area indicate that the lower reach of the unnamed creek may have bxm diverted by runway fill near the southwest end of the runway. Rosalie Creek enters the lake approximately 500 m south of the FPLA facility and drains an area south of the u m d creek drainage basin.

The mean annual precipitation was estimated from a map of mean annual preciptation for Alaska and conterminous basins of Canada (Jones and Fahl, 1994, plate 2). In the tkee srnall stream basins, the mean annual precipitation is approximately 533 nun (2 1 in.). The larger drainage area of the North Fork of the Chandalar River receives approximately 690 mm (27 in.) of prscipi- tation each year.

A single icing approximately 2,000 m long was observed in Tobin Creek at the kead of the alluvial fan during an aerial recomaissanee in 1 972 (C.E. Sloan, U.S. Geological Surv>y, written comun., 1972). Icings, known also as aufeis, are masses of ice formed by the breakout, overflow, and subsequent freezing of sheets of emergent surface water and ground water (Sloan and others, 1976). Icings can divert surfacewater flow and cause flooding and erosion if the temperature rises quickly and substantially, thereby posing a hazard to structures. The icing feature obs3wed near the FAA Chandalar Lake facility is approximately 1 km southeast of the runway's ncrtheastern end. Documented only during the 1972 overflight, it is not known if the Tobin Creek icing occurs annually.

The U,S, Army Corps of Engineers (1993) documents no record of floods in the Chandalar Lake area or of flood insurance studies for the area. The ECR report prepared by EEology and Environment, Inc. (1 992) also documents no flood history at the facility. Lack of floodin r~ was also confirmed by the owner of the neighboring McManus camp (Jack McManus, oral commun., 19951, and by the National Weather Service (P. Meyer, National Weather Semice, oral commlm., 1995). Because these is no history of flooding at the FAA Chandalar Lake facility, a flood frequyncy anal- ysis was not undertaken. However, intense rainfall events in the small drainage basins near the FAA facility might result in short periods of high water in the nearby streams. The l a rp capacity of Chandalar Lake should attenuate floods in the North Fork of the Chandalar River 2 nd reduce any significant threat of flooding to the FPLA facilities, which are about 3 to 4 m above I -ke level.

Ground Water

Ground-water resources at the FAA Chandalar Lake facility have not been explored (Ecology and Environment, Inc., 1992). The facility is in the zone of continuous permafrost (Fersi~ns, 1965), and the distribution of aquifers will be aflwted by the dis~bution of permafrost. Aquifers are rnos t likely to exist in sediments near the lake and in the alluvial fans (Sloan and van Everding sn, 1 988). An aquifer near the lake may remain unfrozen throughout the winter W u s e of the warming effect of the lake water. In the alluvial fans, relatively warm summer stramflow may advect sufficient heat into an aquifer near the streambed to prevent freezing during the winter. Ground w-ater at the facility probably flows west toward Chandalar Lake or south toward the u n n d creel-.

The presence of the large icing in Tobin Creek indicates that base flow continue- after the stream freezes. Base flow, that component of stmamilow contributed by ground water, requires the presence of an aquifer as a water source above the reach where the icing occurs. Therefore, the presence of the icing indicates that an unfrozen aquifer persists in the Tobin Creek watershed above the head of the alluvial fan for at least part of the winter.

DRINKING WATER

Ecology and Environment, Inc., (1992) reported that the McManus camp obtairs drinking water from a water intake in Chandalar Lake. The intake is near the mouth of the unnamed creek, which is approximately 400 rn downstream from a fuel stoxage site at the facility (Ecology and Environment, Inc., 1992). A suspended fuel line crosses the unnamed creek near the scnth end of the runway. Ecology and Environment, hc., while preparing the ECIR in 1992, collrcted three water samples from the unnamed creek that flows immediately south of the facility. Analyses showed that zinc was present in all three samples at concentrations of 1 8 to 5 1 kg/L, an1 lead was detected in the upstream (background) sample at concentrations of 20 pgL (Ecology and Environ- ment, h., 2992). No other surface-water-quality information is available.

Chanddar Lake is an abundant source of drinking water for the area" small seasl7nal popu- lation. The estimated per-capita water withdrawal from mral surfacewater sources for domestic use in Alaska is about 38 Ud (U.S . Geological Survey, 1986). The nearby streams also could pr+ vide water in quantities sufficient to meet the small seasonal needs if Chandalar Lake became con- taminated. However, the streams probably freeze to their streambeds during the v~inter and discharge no water. Snow and ice also provide an alternative water source throughout much of the year if suitable heating and filtering means are available. Ground water might be ava:lable on a year-round basis from unfrozen aquifers beneath and in close proximity to Chandalar Lake. Alter- native water resources may be available in adequate quantity from these local sources to supply a small population should an alternative water supply be required. The quality of ground water in unfrozen aquifers beneath and adjacent to Chanddar Lake probably is good (Sloan, 19197).

SUMMARY

The Federal Aviation Administration facility at Chandalar Lnke is on the east s1 ?re of the lake in the eastern Brooks Range of Alaska. In the continental climate zone, the area has long cold winters and short cool summers. Floods are not a significant threat at the EaciLity. The f-cility and a nearby private lodge currently obtain drinking water from Chandalar Lake. Although alternative water sources exist and may be adequate to supply a small population, their quantity znd quality have not been documented. Surface spills and disposal of hazardous materials could affect the quality of the surface water and ground water in the area.

REFERENCES CITED

Brosg6, W.P., and Reiser, H.N.. 1964, Geologic map and section of the Chandalar quadrangle, Alaska: U.T , Geological Survey Miscellaneous Geologic Investigations Map 1-375, scale 1:250,000.

Ecology and Environment, Inc., 1992. Draft environmental compliance report, Chandalar FAA statior, Chandalar, Alaska: [Copy available through the Environmental Compliance Section, A A L 4 5 , Federal Aviation Adminis- tration, Alaska Regional Office, Anchorage, Alaska.]

Ferrians, 0 J., Jr.. comp.. 1965, Permafrost map of A l m b U.S. Geological Survey Miscellaneous Geologic hvesti- gations Map 1 4 5 , 1 sheet, scale 1:2,500,000. (Reprinted 198 1.)

Hamilton, T.D., 1978, Sur6cial geologic map of the Chandalar quadrangle, Alaska: U.S. Gwlogical Survey Miscella- neous Field Studies Map MF-878-A, scale 1:250,000.

Hartman, C.W., and Johnson, P.R, 1978, Environmental atlas of Alaska: University of Alaska Fairbanla, Institute of Water ReswrcesJEngineering Experiment Station, 95 p.

8 Overvlew of Envlronmantal and Mydrogcrologlc CondItlon8 at Chandalar Lake, Alaska

Jones, S.H., and Fahl. C.B., 1994, Magnitude and frequency of floods in Alaska and conterminous basins of Canada: U.S. Geological Survey Water-Resources Investigations Report 934 179,122 p.

Leslie, L.D.. 1989, Alaska climate summaries (2d ed.): University of Alaska Anchorage, Arctic EnvironmentaI MOT- mation and Data Center, Climate Center Technical Note 5.

Orth, D J., 1%7, Dictionary of Alaska place names: U.S, Geological Survey Professional Paper 567, l,O?Q p.

Rieger, S., Schoephorstex. D.B., and Furbush, C.E., 1979, Exploratory soil survey of Alaska: U.S. Departrrent of Agri- culture. Soil Conservation Service, 213 p.

Schoephorster, D.B., and Mator, FU3,, 1973, Soils of she Chmdalar area, A l h US. Depmment of Agriculture, Soil Conservation Service. 24 p.

Sloan, C.E.. 1987, Water resources on the North Slope, Alaska, in TaiUeur, Xn: and Weirner, Paul. ds., lV7 , Alaskan North Stope geology: Pacific M o n , SEPM and Alaska Geological Society, v, 50, p, 233-252.

Sloan, C.E., and van Everdingen, R.O., 1988, Region 28. Permafmst region, in Back, W., Rosehshein, J.S.. and Seaber, PR., 4s.. Hydrogeology: Boulder, Colo., Geological Society of America, The Geology of North America, v. 0-2, p. 263-270.

Sloan. C.E., anone, Chester, and Mayo, L.R., 1976. Icings along the Trans-Alaska Pipeline route: U.S . GeologicaI Survey hfessiond Paper 979.31 p.

U.S, Army Corps of Engineers. 1993. Alaska communities flood hazards data: U.S. Army Corps of Engireers, Alaska District, 335 p.

U.S. Geological Survey, 1979, Water resources data for Alaska, water year 1978: U.S. Geological Survq Water-Data Reports AK-78- 1 425 p.

1986. National water summary, 1985-HydroIogic events and surface-water resaurces: U.S. Geological Survey Water-Supply Paper 2300, SO6 p.

Viereck, L.A., and Little, E.L.. Jr.. 1972, Alaska trees and shrubs: U.S. Department of Agriculture Handb-mk No, 410, 265 p.

Wahrhaftig, Clyde, 1965, Physiographic divisions of Alaska: U.S. Geological Sutvey ProfessionaI Paper 482,52 p.